The Most Amazing Dream

[Director of the Center for Sleep and Cognition at Harvard Medical School Robert] Stickgold notes that during REM sleep, when dreaming typically occurs, the release of the neurotransmitter serotonin is shut off in the brain. The only other time that happens is because of LSD, "when people seem to have these totally uninteresting experiences they describe as profoundly meaningful called 'acid insights.'"

This sense of meaning may be a physical phenomenon "just like hunger or thirst, save that it's the excitement we feel upon a great insight, that 'Aha!' feeling," Stickgold says. "Who knows why, for instance, fireworks often seem to trigger it — maybe there's something about the geometric patterns that evokes this sense of awesomeness, the feeling that we can almost understand something amazing but not quite that drives us to seek a better understanding of things. It's like what you feel during a religious experience — you sense the oneness of mankind."